Cross-flow jet



Aug.5, 1969 I R. o. NEAL 3,458,890

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ATTORN Y3 v Aug. 5, 1969 R. D. N'EAL'. 3,458,890

CROSS-FLOW JET Filed May 9, 1966 w a Sheets- Sheet s Auk FLOW- 68,-. o o o.

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United States Patent 3,458,890 CROSS-FLOW JET Richard D. Neal, Kingsport, Tenn., assignor to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Continuation-impart of application Ser. No. 518,668

Jan. 4, 1966. This application May 9, 1966, Ser.

Int. Cl. A47! 5/38, 15/00; F26b 11/02 US. Cl. 15306 Claim ABSTRACT OF THE DISCLOSURE This is a continuation-in-part of my copending application Serial No. 518,668 filed January 4, 1966.

This invention relates to an improved apparatus for removing liquid or particles from various types of fibrouslike materials such as those of an elongated, flexible nature as exemplified by filament yarns, spun yarn, wire, plastic strips, tow, tapes, and similar objects. More par ticularly, this invention relates to an apparatus for uniformly removing liquids from continuous filaments of the polyethylene terephthalate class subsequent to drawing in a heated bath and prior to heat-setting.

It is well established in the textile industry that filaments can be produced by extruding polymers through one or more orifices to form filaments, which filaments can be quenched or otherwise treated and collected. It is also well known that the usefulness of such filaments in many instances can be substantially increased by drawing or stretching the filaments to produce molecular orientation along the filament axis.

A number of procedures have been developed and described in prior patents and publications for orienting filaments. For present purposes it is thought adequate to refer to two types of procedures, namely, a dry procedure and a procedure involving a liquid bath. The dry procedure usually involves a series of rolls and a hot device such as a pin around which the filaments are wrapped. The function of the pin or heated surface is to transfer heat to the essentially unoriented filaments thus softening them, and to localize the point of draw to provide more uniform functioning of the stretching process. In the dry procedure the input roll is followed by the heated pin or other heated surface which, in turn, is followed by a second rotating circular member. or output roll that has a greater surface speed than the input roll. Since the yarn is wound about each roll it is thus subjected to a stretching or drawing force as it leaves the heated pin or surface.

While such dry methods are extensively used and apparently have merit on small denier yarns, such dry methods have some limitations. For example, certain fiber-forming polymers exemplified by polyesters do not stretch in such a manner that reduction in diameter occurs along the entire length as in the case of an elastic rubber band. Instead, such linear fiber-forming polymers may Patented Aug. 5, 1969 form a draw-neck in the stretching zone which is a relatively localized section where the filaments rapidly reduce from the original diameter to a permanently reduced diameter while maintaining relatively unoriented yarn of substantially unchanged diameter prior to this draw-neck. As the yarn denier increases, the transfer of heat from the aforementioned heated pin or surface to the yarn becomes increasingly variable thereby causing a non-uniform stretching action with resultant broken filaments, subsequent dye take-up variations, and other deficiencies.

Attention may now be turned to the procedures involving the use of a liquid heating bath. This is the situation wherein the present invention finds its most apparent application. In such wet type processes using a liquid heating bath it is possible to apply relatively simultaneous heating to the filaments over a greater area and thereby obtain better uniformity of treatment. However, such prior processes involving a liquid bath tend to leave a heavy liquid layer on the filaments that adversely affect the quality of the finished filaments.

To eliminate such residual liquid layer various procedures have been proposed, which will for convenience of description be referred to as sling-off, for deleting or removing the liquid layers. The principal objections voiced by the textile industry to these previously known and used devices or systems for removing liquids from a moving flexible material are their: (1) inability to remove liquid uniformly, (2) inability to remove sufiicient liquid, (3) inability to remove liquid properly at speeds below about 1200 yards per minute, (4) inability to properly separate the removed liquid from the path of the yarn, as in the case of jets used in prior art which emit gas along the yarn path, and (5) extreme difiiculty and excessive time required in threading-up these liquid stripper devices.

Accordingly, it is believed apparent that although a large number of procedures for removing a liquid from a moving flexible material have been proposed there is still the need for further process and apparatus which eliminates or minimizes problems of the aforementioned types which may be encountered with currently available pro cedures. After extended investigation I have found a new apparatus which is considerably more versatile than existing apparatus, minimizes substantially all of the prior listed difficulties and otherwise represents a useful contribution to the field of orienting continuous polymeric filaments or like filamentary materials.

Therefore, this invention has for one object to provide a procedure and apparatus for removing liquid-like products from continuous filamentary materials in a manner which is reasonably simple and eflicient, and which overcomes or minimizes certain maior deficiences of previous methods.

Another object is to provide an apparatus for removing liquids from continuous filament yarns wherein a uniform liquid removal can be obtained even with the passage of the yarn through the process at relatively high speeds.

Still another object is to provide a liquid removal apparatus which is utilizable on filaments and y-arns of various deniers from relatively small deniers to relatively large deniers.

Still another object is to provide a relatively highspeed apparatus wherein a liquid layer carried on a moving filamentary or like structure is uniformly and substantially reduced.

A further object is to provided an apparatus in which the liquid layer can be removed from a yarn-like material prior to being heat treated to thereby facilitate uniform and efficient transfer of heat in said subsequent heat treatments without significant increase in friction against the yarn or yarn damage.

A further object is to provide an apparatus wherein the liquid layer can be substantially and uniformly reduced in a relatively low-speed process wherein prior art slingoif devices are not operable.

A still further object is to provide an apparatus wherein residual lubricant and polymer fractions can be removed or reduced after drawing in the heated bath and prior to any desired subsequent yarn treatment.

These and further objects and advantages of this invention will be more apparent upon further reference to the following specification.

In the work on my invention I have made certain observations concerning drafting yarn including the fact that a number of polymeric filaments or yarns made up from a plurality of filaments or fibers may not reduce in size uniformly when heated for orienting and subjected to the drafting or drawing step. That is, as mentioned above, a filament may not sustain a uniform reduction of diameter along its heated length analogous to an elastic band. Instead, the filament may tend to form a draw-neck in the stretch zone. Any lack of uniformity in the control of the formation of this draw-neck may later be evidenced in several respects.

Woven or knitted cloth produced from yarns containin such filaments frequently and unpredictably exhibit a streaky appearance in varying degrees of intensity. This same cloth often exhibits a flash condition of varying degrees. Flashes are defined herein as undrawn sections of one or more filaments, usually but not always less than -inch in length, which dye darker and have a larger diameter than the drawn portions of the filaments.

I have observed the intensity of streaks to be directly related to a considerable degree to the variability of the tension in the stretching zone. Tension recordings made by a tension analyzer (Model BL825) at 100 cycles/ second recording response in the stretch or draw zone have shown that the tension level may change rapidly over a relatively wide range when yarn is drawn by a socalled heated pin process wherein the pin is not submerged in a liquid bath. It is thought that tension variation of certain prior art processes may be due primarily to variable friction drag of the yarn over the relatively dry heated surface. My observations have indicated that a stick-slip effect frequently occurs as yarn slides over a heated surface thus incurring changes in draft tension that often fall within the range of 50 to 100 cycles/second. Comparative studies carried out on the process and apparatus of the present invention indicate that the tension trace of yarn drafted by the process of the present invention is significantly less variable.

Since uniformity of dye take-up and several other properties depend as just explained at least in part on the uniformity of crystallization and orientation of the filaments it follows that uniform heat transfer to the filaments in the draw zone and in the heat-setting zone is desirable in order to achieve equal heat exposure of the filaments. I have observed that the arrangement of the filaments in the yarn varies as the filamentary bundle slides around or across a heated surface in the draw zone with the filaments sometimes spreading apart and sometimes st-acking or crossing over. Therefore, in certain prior processes and apparatus the outermost filaments do not touch the heating surface at all or are temporarily insulated therefrom for this reason or other reasons as will be further apparent as the description of my invention proceeds.

It is already known to some extent that the employment of a liquid heating bath will provide a greater area and length of yarn heating. This most abundant heating can be obtained not only by using a heating media as hot Water but hot oils and a variety of liquid heating media can be employed on the degree of temperature and amount of heat exposure it is desired to impart to the yarn. However, such heating with a liquid bath necessarily brings the filaments or fibers making up the yarn into .4 direct contact with the liquid. Hence, upon the filaments leaving the heating bath there is carried on the surface of the filaments some amount of the liquid. Although a major portion of this residual coating liquid may be removed by conducting the yarn through a slot, against a sponge or the like expedient employed, not all of the liquid is removed. Therefore, the aforementioned slingoff procedures have been employed. As already referred to, at the relatively high yarn speeds required for obtaining liquid sling-off the yarn in passing at an angle about pins or guides may be damaged as manifested by broken filaments, tangled skin-backs, excessive tension, and other defects. Also, even with high speed operations sufiicient residual liquid may not be removed and there can still remain a relatively reduced but significant layer of liquid often exceeding 2.5 percent based on the weight of the yarn. Such layer even if minute when the yarn is contacted with a further heater for heat-setting may tend to at least temporarily insulate the yarn from such heatsetting operation. Or, in the event certain liquids are used such heat-setting may tend to cause spasmodic, gummy deposits on the yarn or heater, or otherwise present problems.

In the broader aspects of my invention I have discovered not only how to employ various types of liquid heating baths but to be able to relatively fully remove any residual liquid from the surface of the filaments which have been immersed in such heating baths. Hence, in my invention filaments, fibers and yarns may not only be more uniformly heated and more uniformly drafted, but upon removal of the yarn from the liquid heating bath in my apparatus I am able to substantially remove the residual liquid over an extremely wide range of yarn speeds. Hence, upon my drafted yarn being passed to a heat-setting step, difiiculties because of residual liquid are nonexistent and a better quality yarn can be produced.

For a further understanding of the present invention reference is made to the attached drawings forming a part of this application wherein:

FIGURE 1 is a semidiagrammatic elevation view of the overall apparatus useful in the liquid bath drafting of y FIGURE 2 is a side elevation view of a device which may be included in my apparatus setup for substantially fully removing residual liquid;

FIGURE 3 is a section taken on line 33 of FIG- URE 2;

FIGURE 4 is a section taken on line 4-4 of FIGURE 3; and

FIGURE 5 is a section taken on line 55 of FIG- URE 2.

With continued reference to the accompanying figures wherein like reference numerals designate similar parts throughout the various views, and with initial attention directed to FIGURE 1, it can be seen that my apparatus includes an input roll assembly 10 and an output roll assembly 12. Inasmuch as these roll assembies may be comprised of parts well known in the textile industry detailed description appears unnecessary. It is believed sufiicient to state that such roll assemblies may have in association therewith other rolls as pinch roll 14 shown in association with input roll 10. Roll 14 can be used to hold the undrawn yarn 16 firmly in contact with the driven input roll 10. Or, if desired, multiple wraps of the yarn (filaments) around an idler roll 18 and the driven input roll 10 can be used so as to deliver the undrawn yarn 16 at the surface speed of the input roll 10.

The undrawn yarn 16 is obtained from a suitable sup ply source 20, the details of which are not shown on the drawing. That is, the supply source may be a spinning machine or it may be a package of yarn such as a parallel package or cone.

In the event the supply yarns comprise more than one end an input guide 22 may be provided as indicated for better supplying the several ends to the input roll. Inasmuch as the procedures for feeding one or more ends of yarn to an input roll for drafting apparatus are known, further description of this portion of my apparatus is unnecessary.

The undrawn yarn from the input roll as just referred to is conducted into a heated liquid bath 24 which contains a fixed pin 26 or other equivalent device. This liquid bath 24 may be equipped with various heating and/or cooling devices, inlet and outlet pipes for the liquid and the like (not shown) for permitting the control of the temperature, flow rate, and level of the bath. Here again, since such elements in connection with a liquid bath are known, extended description appears unnecessary.

The draw pin 26 just referred to is at least partially submerged in the liquid bath 24. The undrawn yarn 16 as above stated passes from the supply to a tensioning means if desired, to aforesaid input roll and then into contact with the draw pin 26 which is at least partially submerged in the liquid bath 24. The undrawn yarn 16 commences heating on the input side of the pin 26 and is drawn or drafted to the desired degree as will be explained and further apparent from the examples while the localized initial point of the draw remains confined to a location which is reached by the yarn subsequent to entry into the bath or contact with pin 26.

At approximately the zone 28 the yarn has emerged from bath 24 as drawn yarn 30. As will be explained in more detail in connection with FIGURES 2 through 5, the heated, wet yarn 30 passes through liquid stripping devices 32 and 34 constructed in accordance with this invention wherein residual liquid from the liquid bath 24 is removed.

Referring further to FIGURE 1, the drawn yarn 30 then passes in contact with output roll 12 and subsequently to a heated plate device 36 for heat-setting or further heating purposes. Above this heat-setting zone 36 there is positioned an idler roll 38 covered by exhaust hood 40. The hot air rising from the plate 36 may be removed through exhaust hood 40 to prevent undue heating of the room and equipment.

The drawn and heated yarn passing around heat resistant idler 38 then is wrapped one or more turns around the output roll assembly 12 already referred to. This output roll assembly may include one or more idler rolls exemplified by 18 as well as a relubricating roll designated 42. Inasmuch as the construction and function of such rolls are already known in the industry further description appears unnecessary. In addition, it is readily understood that any convenient heating means, such as a skewed heated roll, may be used to accomplish the same purpose as plate 36 and idler 38. Such substitutions are common to the art and the choice of such heating means often is dictated by the speed at which the process is to be operated. The drafted and heat-set yarn 44 may be removed from my apparatus as shown at 46 after which it passes to any convenient take-up means.

Reference is now made to FIGURES 2 through 5 concerning a device constructed in accordance with this invention which may be used to substantially remove residual heated liquid 24 from the drawn yarn 30.

I have found it highly desirable in water-drafting systems that the heating liquid remaining on the yarn be reduced as much as possible and at least to about 0.75% or less percentage based on the weight of the dry weight of the yarn for deniers less than about 300. For deniers above 300, a residual moisture of up to 2.5% can in some cases be tolerated. This is true since, with an essentially constant heat input rate, the temperature rise below the boiling point of a liquid varies inversely with its volume for any given unit of time. Also, the boil-off time of a liquid varies directly with volume with an essentially constant heat input. Thus, it can be clearly established that variable residual moisture on the yarn causes some sections of the yarn to reach plate temperature more slowly than others, leaving relatively less plate contact length (which is, of course, representative of heat exposure time) in which to achieve heat-setting. The heat-setting step, in turn, induces increased yarn crystallinity which is necessary in the production of a stable textile product. Therefore, since dye take-up of the yarn varies inversely with crystallinity, it can be shown that variable moisture content on the yarn, through interaction with heat-setting, produces variable dye take-up which causes relatively light and dark lengths of yarn with a resultant strea'ky appearance in the dyed fabric. An economic and engineering factor to consider is that a reduced level of residual moisture allows the yarn to reach the required heat exposure in a shorter time, thus a shorter plate or, in some cases, lower temperatures can be used.

Therefore, it can be seen why this reduction of liquid should be made prior to the yarn being heat-set as, for example, by being brought into contact with the heated plate 36 of FIGURE 1. If the yarn 30 contains variable residual moisture the contact time required to reach a given temperature in traveling across plate 36 will vary because the plate must heat the liquid before the heat can be transferred to the filaments. In the case of water, the liquid must be boiled off before the temperature of the yarn can rise above C. The removal of liquid may be accomplished to a preliminary extent by passing the oriented yarn 30 through a skimming means 32 as shown in FIGURE 1. The use of such a skimming means is highly desirable since the yarn normally pulls a heavy and variable stream. of water (100 to 200 percent or more based on the yarn weight) from the drafting bath. This skimming means can be a slot-ted sponge, a narrow slot, or even a bed of glass beads. Such skimming means serves to remove a portion of the heavy stream of liquid but will leave approximately 5 to 12 percent liquid on the yarn 30. Removal of this residual liquid without damage and without using a sling-oh procedure may be accomplished by the invention as illustrated in FIGURES 2 through 5. The device of these figures is for convenience referred to as a cross-flow jet 34 and may be positioned somewhere along the path of the oriented yarn 30 as shown, for example, in FIGURE 1.

This cross-flow jet 34, which is illustrated on an enlarged scale in FIGURES 2 through 5, includes a housing that is formed from an upper or inlet body portion 48 and a lower or outlet body portion 50. These shells or body portions 48 and 50 are made of stainless steel, brass, aluminum, plastic or other corrosion and rust-resistant material which can be machined or molded to the desired shape and required tolerance. For ease of construction, adjustment, or disassembly for repair, cleaning or other purpose the inlet and outlet portions of the cross flow jet are held together by bolts 52 and 54.

As more clearly seen in FIGURES 3 through 5, the inlet portion 48 has a plenum chamber 56 machined out of or otherwise formed therein. This chamber is equipped with an inlet conduit 58 for the receipt of air or other gas under pressure such as nitrogen, or any desired mixtures of gases. A plurality of small outlet ports or jet orifices 60, which are circular or elongated holes carefully drilled, punched, or molded so as to emit a high velocity gaseous flow in a substantially perpendicular relationship to the path of the material 30 being treated, are provided on the lower side of the chamber 56. The cross-flow jet unit 34 shown in these figures employs three of these jet orifice holes '60 arranged in a substantially straight line as followed by the material 30 being treated, but any desired number can be used.

In order to exhaust the gas which has passed across the oriented yarn 30 and removed residual liquid therefrom there is provided an exhaust chamber 62 within the outlet body portion 50, the function of which is thought readily apparent from a mere inspection of FIGURE 4 that shows the liquid-laden gas traveling toward the exhaust tube or conduit 64. If desirable, the upper portions 62' of this chamber can be circular in shape with yarn guide edges 63 formed thereon. Preferably, chamber 62 is maintained under a partial Vacuum by suitable pumping means to increase the efliciency of cross-flow jet unit. For cleaning and maintenance purposes an access plug 66 is provided at the end of the exhaust chamber 62. A suitable mounting plate 68 or other means can also be provided on the outlet body portion for suitably securing the crossflow jet in my apparatus combination.

As can be seen in FIGURE 3, when the inlet and outlet body portions 48 and 50 are secured together to form a housing by the bolts 52 and 54 a L-shaped yarn passageway 70 is formed between the portions. This permits the yarn 30 to be readily threaded through the cross-flow jet simply by pulling the yarn past the jet and then slipping it sideways into the passageway.

For reasons that will be more fully set forth hereinbelow, it is desirable to include yarn guides 72 and 74 adjacent the yarn passageway 70 at the point where the yarn 30 both enters and leaves the cross-flow jet 34. Each of these guides consists of an adjustable plate 76 which has an elongated slot 78 formed therein and is movably secured to the inlet body portion 80 by a boltlike fastener means 82. A pair of pins 84 and 86 is mounted on each, plate 76 in a plane substantially perpendicular to both the direction of the gas flow through the orifices 60 and the length of the yarn flowing through the cross-flow jet. As will be apparent, the axis of each pin is oflset by a sufficient amount to permit the yarn 30 to pass under one pin (for example pin 84) and over the other pin (86) without being appreciably deflected. A separation guide pin 88 is mounted in a plane substantially perpendicular to the path of the yarn and in the direction of the gas flow through the orifices. An internal guide pin 90 is mounted within the exhaust chamber 62 in a plane substantially perpendicular to both the direction of gas flow through the orifices 60 and the length of the yarn flowing through the cross-flow jet. For best results, it is desirable that the guide pins be made of ceramic or some other equally smooth, wear-resistant material.

As can be seen from viewing FIGURES 4 and 5, the yarn guides 72 and 74 can be moved in a plane parallel with the direction in which the gas from orifices 60 is flowing by simply loosening the fastener means 82 and slipping the adjustable plate 76 in the desired direction. Thus, by this adjustment the angle, it any, produced as the wet yarn 30 passes over the internal guide pin 90 can be adjusted to any desired value. The advantages of this arrangement will be more fully explained hereinbelow.

If desirable, a movable mounting block 92 can be used to carry guide pin 88 so that the position of this pin can be adjusted, as by turning a set screw drive 94, to any position desired before the entrance 96 (see FIG- URE and exit 98 of passageway 70. This permits the guide pin 88 to be used to center the yarn 30 over the orifices 60 as it passes through the exhaust chamber 62. Furthermore, if two or more yarns 30-30 (sec FIGURE 5) are to be simultaneously treated, the guide pin 88 serves to not only center the yarns, but to keep them properly separated.

The operation of the cross-flow jet 34 can be described substantially as follows: The single or multiple strands of the wet fibrous-like material or yarn are positioned in the passageway 70 and around the yarn guide pins in the manner illustrated in the various figures. The yarn is thus positioned directly below the orifices 60. A source of gas under suitable pressure, such as from a pumping unit, is now connected to the inlet conduit 58 while, preferably, a vacuum unit is operatively connected to the outlet conduit 64.

With the pressure and vacuum sources turned on the gas that is to be used to treat the yarn will be forced through inlet conduit 58 into the chamber 56 as a high velocity stream, then through orifices 60 thereby passing perpendicularly across the yarn. The gas perpendicu- 8, larly passing across the yarn 30 forces the liquid free of the yarn, usually in the form of a fine mist or aerosol, in an abrupt or substantially right angle departure from the yarn path. The liquid laden gas is then expelled or otherwise exhausted through exhaust chamber 62 and out exhaust tube 64. A suction applied at exhaust tube 64 is of significant benefit in increasing the efliciency of liquid removal since this suction reduces the back pressure at exhaust chamber 62 thus preventing build-up of moisture laden gas which would re-wet the yarn, and also would tend to reduce the net efiective pressure drop of the gas flowing through orifices 60.

The amount of liquid removed is related to the pressure of the gaseous medium to a signficant degree, but it has been found that the efiiciency of liquid removal can be increased substantially by using internal positioning pin 90. Pin 90, which holds the yarn 30 at the desired distance from the jet orifices 60 and also has a skimming action, produces satisfactory liquid removal at reduced gas pressure levels. When positioned properly pin causes the yarn to be deflected slightly against the direction of gas flow and thus flattened on the pin surface. The liquid coats the pin 90 and would of course tend, in the absence of gas flow, to reach equilibrium state in re-wetting the yarn 30 minus Whatever amount would fall from the pin in droplet form. However, no such equilibrium is permitted to occur because the flow of gas from the center orifice 60' (see FIGURE 5) constantly strips pin 90 of this liquid coating and forces liquid thus removed toward exhaust chamber 62.

In a preferred embodiment of the cross-flow jet the yarn 30 is positioned 51 -inch from the jet orifices 60 and passes across the central two-thirds portion of the orifice diameters. For dual ends of yarn about 300 denier each or less, air jet orifice diameters of -inch are satisfactory. The exhaust chamber 62 has been designed to form a positioning slot or passageway 70 which holds the yarn in the desired relationship across the central portion of the jet orifices and also provides a thread-up path for rapid initial positioning of the yarn end or ends. By merely placing the yarn 30 on the extended bottom portion of the entrance to slot 70, and then pushing to the rear of the slot 70, the yarn 30 automatically slides across and down into the correct position in slot 70.

While it is believed that the operation of my apparatus is already understandable to a substantial extent from the preceding apparatus description, a brief description of the process will now be set forth referring back to FIGURE 1. It should be realized, however, that the crossflow jet unit 34 of this invention has been found to have a variety of useful functions in addition to liquid removal and that the description of the cross-flow jet in a wetyarn drawing process represents but one of the systems in which the jet can be employed.

The yarn to be oriented is fed into my apparatus around a suitable guide or tension device 22. Usually several turns of the yarn will be made around the input roll 10 and idler 18 to prevent slippage. The prevention of slippage may be augmented by pinch roll 14. The yarn is then passed in contact with the submerged pin 26 in bath 24.

The bath 24 is of a composition compatible with the nature and composition of the polymeric yarn to be processed. In many instances clean water relatively free of mineral compounds, chlorine or other contaminants is a satisfactory heating media. The temperature to which the heated liquid media is raised will likewise depend to some extent on the composition of the polymeric yarn being processed. If it is desired to heat the yarn to temperatures above 100 C. then liquid baths comprised of mineral oils, glycols, salt solutions and the like may be used.

The yarn from pin 26 is threaded through skimming device 32 and cross-flow jet 34. It is then threaded about roll 12 and over the heat-setting plate 36 around idler 38 9 to the output roll 12. At output roll 12 it is preferred to place several turns of the yarn around the output roll and idler mechanism in order to eliminate slippage. By operating output roll 12 at a greater speed than the input roll the degree of drafting desired may be accomplished whether it be a few percent or several hundred percent.

Inasmuch as any residual liquid including any yarn lubricants initially applied to the yarn may have been significantly reduced in the cross-flow jet unit 34, it may be desirable to include a further lubricant on relubricating roll 42. This relubrication may be more or less a conventional operation and any convenient devices can be used in place of the roll 42. The resultant drawn and heat-set yarn 44 may be removed from my apparatus to package windup or the like in the vicinity of 46.

A further understanding of the invention will be had from a consideration of the following examples that may be used in actual commercial practice and are set forth to illustrate certain preferred embodiments.

Example 1 Dual ends of 70-33-0 polyethylene terephthalate were drafted in a hot water bath substantially as shown in FIGURE 1. A cross-flow jet pressure series was run to demonstrate the effectiveness of water removal of a triple-orifice unit as shown in FIGURES 2 through 5. A single /s-inch diameter vertical positioning pin 88 was used prior to entry into the jet to separate the ends and a Ar-inch diameter internal positioning pin 90 was used to maintain a yarn-to-orifice distance of -inch and to increase the jet efiiciency. Except for the small contact angles on pins 88 and 90 (less than 10), the yarn path from draw pin 26 through the cross-flow jet 34 to roll 12 was substantially a straight line. Plate 36 was intentionally used at room temperature to avoid drying the yarn 30 because the purpose of this test was to determine the amount of moisture remaining on the yarn 30 after leaving the cross-flow jet 34 and before contact with the plate 36 which is normally heated to above 120 C. to heatset (crystallize) the yarn.

The yarn was drafted in a heated water bath 24 (90 C.) at 900 y.p.m. output speed at a draw ratio of 3.91. A slotted sponge was used as the preliminary skimming device 32. The percent moisture remaining after passage through the jet is shown for different jet air pressures in the following Table 1:

TABLE 1 Percent residual moisture Yarn and 1 Yarn end 2 Air pressure at in ut (p i The degree and uniformity of liquid removal obtained at 21, 24, and 27 p.s.i.g. are superior to the results obtained by any method or combination of methods previously tested. An unexpected advantage of this invention is that a significant amount of monomer is removed with the liquid. This is especially desirable since, as is well known in the textile art, monomers deposited during knitting, warping, etc., can be detrimental to quality as well as a nuisance to clean.

Example 2 orifice at a distance of -inch from the orifice outlets.

The cross-flow jet of this invention has been found in extensive testing to offer the following advantages and improvements over other heretofore known and used methods and devices:

(1) Liquid is removed uniformly, thus facilitating uniform results in any subsequent yarn heat treatments.

(2) Without damaging the yarn, the residual yarn moisture can be reduced to less than about 0.75% from an initial level of at least 12%, thus eliminating any need to sling off or dry the liquid from the yarn.

(3) The cross-flow jet is effective over a wide range of yarn speeds by simply adjusting the pressure of the gaseous medium.

(4) The liquid removed is carried away from the yarn path, thus avoiding re-contamination of the yarn by drippage and spray fall-out. Another advantage of this crossflow or perpendicular, liquid-removal direction is that contamination of the room atmosphere is prevented since the moisture-laden gaseous flow is conducted into an exhaust system and does not spray out along the yarn path into the area on the exit side of the jet.

(5) The apparatus of this invention is easily disassembled for periodic inspection, cleaning or adjustment. Such servicing procedures are seldom required, however, and the jet can be satisfactorily cleaned by merely pouring hot Water (70 C.) over the yam-contact surfaces.

(6) The cross-flow jet has no moving parts and when proper Wear-resistant materials are used the device will have an extremely long life even when relatively abrasive materials like polyethylene terephthalate are treated.

(7) The gaseous medium can be heated or cooled as desired to produce a thermal treatment that is performed simultaneously with the liquid removal or as a thermal treatment alone.

(8) A significant amount of monomer and other residual polymer fractions can be removed from the yarn surface simultaneously with liquid removed.

(9) More than one strand of yarn can be treated in a single jet.

(10) The pressure of the gaseous medium can be altered in a pattern or in random fashion to produce novelty effects by subsequent heat-treatments of the yarn to create differential shrinkage or dyeing.

(11) When used on the output side of a yarn-lubricating system, such as a dip bath or contact roll, the crossflow jet furnishes a convenient means of removing and collecting excess lubricant as Well as leaving an extremely uniform residual lubricant level on the yarn. In similar yarn treatments, fiber particles, solvents, powders, acids, and the like can be removed, reduced or held at a uniform residual level.

(12) The cross-flow jet is effective over a wide range of deniers with no modification other than a simple change in pressure.

(13) In cases where friction is a factor in yarn damage, such as drafting in a bath at speeds greater than about 600 yards per minute, the ability of the cross-flow jet to remove liquid without requiring that the yarn be subjected to considerable snubbing is a major advantage over a number of the prior art methods which require that the yarn pass, at angles up to about over one or more pins which are designed to throw-off liquid by centrifugal force.

(14) Increased output speeds can be achieved with this invention with no sacrifice in properties or cloth appearance. Speeds at least as high as 2800 y.p.m. can be obtained.

(15) The quality of the yarn with regard to slubs and broken filaments is protected by the use of the cross-flow jet for liquid removal which allows an essentially straight path from the draw pin to the output roll to be used.

(16) The cross-flow jet has the major advantage of simple and rapid initial thread-up. No unusual skill on the part of the operating personnel is required because thread-up consists merely of passing the yarn into a slot.

in which it automatically slides into the correct position. The simplicity of this method and the yarn protection provided by the absence of snubbing are of particular importance in operations where the thread-up speed exceeds about 600 y.p.m.

Thus the ability of my apparatus to remove these substances offers a major advantage over the yarns produced by prior art methods.

What is claimed and desired to be secured by United States Letters Patent is:

1. Apparatus for removing residual liquids from moving fibrous-like products comprising:

a housing having inlet and outlet body portions, the

inlet and outlet body portions being separate elements adapted to be mated together and held by suitable fastening means to form said housing;

a chamber formed in said inlet body portion into which a gas can be introduced under pressure;

a product passageway defined by a plurality of similarly contoured spaced surfaces on said inlet and outlet body portions suitable to accommodate a fibrouslike product for longitudinal movement therethrough;

at least one port connecting said inlet body portion with said product passageway and said outlet body portion for directing said gas in a substantially perpendicular direction to and across said passageway.

to thereby remove residual liquids from the moving product;

said product passageway comprising an entrance and a slot contiguously arranged so that the product can be threaded therein by inserting same laterally with respect to its direction of movement during operation;

an exhaust chamber formed in said outlet body portion in communication with said product passageway and into which said gas and removed residual liquids are directed for collection and further treatment;

at least one pin being located in said housing in such manner as to extend across said product passageway and being adapted to guide the fibrous-like product as it moves through the passageway; and

additional guide means being located outside of said housing adjacent to said product passageway and adapted to position and to guide said fibrous-like product as it enters and exits the housing, the additional guide means being adjustably secured to said housing, and said pin and said additional guide means being positioned to maintain the fibrous-like product approximately -inch from said at least one port.

References Cited UNITED STATES PATENTS 1,375,663 4/ 1921 Ainsworth. 2,242,144 5/ 1941 Runton. 2,746,169 5/1956 Bakker 34154 XR 3,191,210 6 1965 Fischer 15307 1,251,173 12/1917 Beregh 34-460 FOREIGN PATENTS 562,192 8/ 1923 France.

ROBERT W. MICHELL, Primary Examiner US. Cl. X.R. 34-154, 

